BackController.js

class BackController extends Component {
  static propTypes = {
    onBack: PropTypes.func.isRequired
  }

  componentDidMount = () =>
    BackHandler.addEventListener('hardwareBackPress', this.handleBack)

  componentWillUnmount = () =>
    BackHandler.removeEventListener('hardwareBackPress', this.handleBack)

  handleBack = () => this.props.onBack()

  render = () => null
}

NavController.js

class NavController extends Component {
  static propTypes = {
    show: PropTypes.bool.isRequired,
    showNav: PropTypes.func.isRequired,
    hideNav: PropTypes.func.isRequired
  }

  componentDidMount = () =>
    this.props.show
      ? this.props.showNav()
      : this.props.hideNav()

  componentWillReceiveProps(nextProps){
    if(!this.props.show && nextProps.show)
      this.props.showNav()
    if(this.props.show && !nextProps.show)
      this.props.hideNav()
  }

  componentWillUnmount = () =>
    this.props.show && this.props.hideNav()

  render = () => null
}

SomeView.js

class SomeView extends Component {
  handleBack = () => {} // ? Do some navigation logic ?
  render = () => (
    <View>
      <BackController onBack={this.handleBack} />
      <NavController show />
      <Text>Some text</Text>
    </View>
  )
}